[BAEL-4849] Article code (#10566)

kubernetes/k8s-intro/pom.xml

@@ -16,6 +16,12 @@
             <artifactId>client-java</artifactId>
             <version>11.0.0</version>
         </dependency>
+
+        <dependency>
+            <groupId>ch.qos.logback</groupId>
+            <artifactId>logback-classic</artifactId>
+            <version>1.2.3</version>
+        </dependency>
     </dependencies>
 
     <build>

kubernetes/k8s-intro/src/main/java/com/baeldung/kubernetes/intro/ApiInvoker.java

@@ -0,0 +1,11 @@
+package com.baeldung.kubernetes.intro;
+
+import io.kubernetes.client.openapi.ApiCallback;
+import io.kubernetes.client.openapi.ApiException;
+import io.kubernetes.client.openapi.apis.CoreV1Api;
+import okhttp3.Call;
+
+@FunctionalInterface
+public interface ApiInvoker<R> {
+    Call apply(CoreV1Api api, ApiCallback<R> callback) throws ApiException;
+}

kubernetes/k8s-intro/src/main/java/com/baeldung/kubernetes/intro/AsyncHelper.java

@@ -0,0 +1,74 @@
+package com.baeldung.kubernetes.intro;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.Future;
+import java.util.function.BiFunction;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import io.kubernetes.client.openapi.ApiCallback;
+import io.kubernetes.client.openapi.ApiException;
+import io.kubernetes.client.openapi.apis.CoreV1Api;
+import okhttp3.Call;
+
+public class AsyncHelper<R>  implements ApiCallback<R> {
+    
+    private static final Logger log = LoggerFactory.getLogger(AsyncHelper.class);
+    
+    private CoreV1Api api;
+    private CompletableFuture<R> callResult;
+    
+    private AsyncHelper(CoreV1Api api) {
+        this.api = api;
+    }
+    
+    public static <T> CompletableFuture<T> doAsync(CoreV1Api api, ApiInvoker<T> invoker) {
+        
+        AsyncHelper<T> p = new AsyncHelper<>(api);
+        return p.execute(invoker);
+    }
+    
+    private CompletableFuture<R> execute( ApiInvoker<R> invoker) {
+        
+        try {
+            callResult = new CompletableFuture<>();
+            log.info("[I38] Calling API...");
+            final Call call = invoker.apply(api,this);
+            log.info("[I41] API Succesfully invoked: method={}, url={}",
+              call.request().method(),
+              call.request().url());
+            return callResult;
+        }
+        catch(ApiException aex) {
+            callResult.completeExceptionally(aex);
+            return callResult;
+        }
+    }
+
+    @Override
+    public void onFailure(ApiException e, int statusCode, Map<String, List<String>> responseHeaders) {
+        log.error("[E53] onFailure",e);
+        callResult.completeExceptionally(e);
+    }
+
+    @Override
+    public void onSuccess(R result, int statusCode, Map<String, List<String>> responseHeaders) {
+        log.error("[E61] onSuccess: statusCode={}",statusCode);
+        callResult.complete(result);
+    }
+
+    @Override
+    public void onUploadProgress(long bytesWritten, long contentLength, boolean done) {
+        log.info("[E61] onUploadProgress: bytesWritten={}, contentLength={}, done={}",bytesWritten,contentLength,done);
+    }
+
+    @Override
+    public void onDownloadProgress(long bytesRead, long contentLength, boolean done) {
+        log.info("[E75] onDownloadProgress: bytesRead={}, contentLength={}, done={}",bytesRead,contentLength,done);
+    }
+}
+

kubernetes/k8s-intro/src/main/java/com/baeldung/kubernetes/intro/ListNodesAsync.java

@@ -0,0 +1,50 @@
+/**
+ * 
+ */
+package com.baeldung.kubernetes.intro;
+
+
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.TimeUnit;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import io.kubernetes.client.openapi.ApiClient;
+import io.kubernetes.client.openapi.apis.CoreV1Api;
+import io.kubernetes.client.openapi.models.V1NodeList;
+import io.kubernetes.client.util.Config;
+
+/**
+ * @author Philippe
+ *
+ */
+public class ListNodesAsync {
+    
+    private static Logger log = LoggerFactory.getLogger(ListNodesAsync.class);
+    /**
+     * @param args
+     */
+    public static void main(String[] args) throws Exception {
+        
+        // Initial setup
+        ApiClient client  = Config.defaultClient();
+        CoreV1Api api = new CoreV1Api(client);
+        
+        // Start async call
+        CompletableFuture<V1NodeList> p = AsyncHelper.doAsync(api,(capi,cb) ->
+          capi.listNodeAsync(null, null, null, null, null, null, null, null, 10, false, cb)
+        );
+        
+        p.thenAcceptAsync((nodeList) -> {
+            log.info("[I40] Processing results...");
+            nodeList.getItems()
+            .stream()
+            .forEach((node) -> System.out.println(node.getMetadata()));
+        });
+        
+        log.info("[I46] Waiting results...");
+        p.get(10, TimeUnit.SECONDS);
+    }
+
+}

kubernetes/k8s-intro/src/main/java/com/baeldung/kubernetes/intro/ListPodsPaged.java

@@ -0,0 +1,46 @@
+/**
+ * 
+ */
+package com.baeldung.kubernetes.intro;
+
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import io.kubernetes.client.openapi.ApiClient;
+import io.kubernetes.client.openapi.apis.CoreV1Api;
+import io.kubernetes.client.openapi.models.V1NodeList;
+import io.kubernetes.client.openapi.models.V1PodList;
+import io.kubernetes.client.util.Config;
+
+/**
+ * @author Philippe
+ *
+ */
+public class ListPodsPaged {
+    
+    private static final Logger log = LoggerFactory.getLogger(ListPodsPaged.class);
+
+    /**
+     * @param args
+     */
+    public static void main(String[] args) throws Exception {
+        
+        ApiClient client  = Config.defaultClient();
+        CoreV1Api api = new CoreV1Api(client);
+        String continuationToken = null;
+        int limit = 2; // Just for illustration purposes. Real world values would range from ~100 to ~1000/page 
+        Long remaining = null; 
+        do {
+            log.info("==========================================================================");
+            log.info("Retrieving data: continuationToken={}, remaining={}", continuationToken,remaining);
+            V1PodList items = api.listPodForAllNamespaces(null, continuationToken, null, null, limit, null, null, null, 10, false);
+            continuationToken = items.getMetadata().getContinue();
+            remaining = items.getMetadata().getRemainingItemCount();
+            items.getItems()
+              .stream()
+              .forEach((node) -> System.out.println(node.getMetadata()));
+        } while( continuationToken != null );
+    }
+
+}

kubernetes/k8s-intro/src/test/java/com/baeldung/kubernetes/intro/ListNodesAsyncLiveTest.java

@@ -0,0 +1,10 @@
+package com.baeldung.kubernetes.intro;
+
+import org.junit.jupiter.api.Test;
+
+class ListNodesAsyncLiveTest {
+    @Test
+    void whenListNodes_thenSuccess()  throws Exception {
+        ListNodesAsync.main(new String[] {});
+    }
+}

kubernetes/k8s-intro/src/test/java/com/baeldung/kubernetes/intro/ListPodsPagedLiveTest.java

@@ -0,0 +1,10 @@
+package com.baeldung.kubernetes.intro;
+
+import org.junit.jupiter.api.Test;
+
+class ListPodsPagedLiveTest {
+    @Test
+    void whenListPodsPage_thenSuccess()  throws Exception {
+        ListPodsPaged.main(new String[] {});
+    }
+}

kubernetes/k8s-intro/src/test/resources/logback.xml

@@ -0,0 +1,11 @@
+<configuration>
+  <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+    <encoder>
+      <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern>
+    </encoder>
+  </appender>
+
+  <root level="debug">
+    <appender-ref ref="STDOUT" />
+  </root>
+</configuration>